Automatic control system for a kitchen warewasher

• US 20070034236A1
• Filed: 08/15/2005
• Published: 02/15/2007
• Est. Priority Date: 08/15/2005
• Status: Active Grant

• Current Assignee: Diversey Incorporated (Sealed Air)
• Original Assignee: JohnsonDiversey, Inc
• Inventors: Reichold, Kurt
• Granted Patent: US 7,691,209 B2
• Time in Patent Office: Days
• US Class Current: 134/18
• CPC Class Codes: A47L 15/0049 Detection or prevention of malfunction, including accident prevention arrangements to prevent clogging of filters A47L15/4208; safety arrangements for preventing water damage A47L15/421
• CPC Class Codes: A47L 15/0081 with vertical sliding closing doors, e.g. hood-type dishwashers
• CPC Class Codes: A47L 15/4219 Water recirculation A47L15/0078 takes precedence
• CPC Class Codes: A47L 15/46 Devices for the automatic control of the different phases of cleaning ; Controlling devices A47L15/449 takes precedence
• CPC Class Codes: A47L 2401/023 Quantity or concentration of the consumable product
• CPC Class Codes: A47L 2401/06 Water supply, circulation or discharge information water level A47L2401/09; water pressure or flow rate A47L2401/14
• CPC Class Codes: A47L 2401/09 Water level
• CPC Class Codes: A47L 2401/12 Water temperature
• CPC Class Codes: A47L 2401/22 Number of operational cycles
• CPC Class Codes: A47L 2501/26 Indication or alarm to the controlling device or to the user
• CPC Class Codes: A47L 2501/32 Stopping or disabling machine operation, including disconnecting the machine from a network, e.g. from an electrical power supply

Abstract

An apparatus reminds an operator of a need to change water in a reservoir of a warewasher. A counter that counts operating cycles of the warewasher and a sensor provides signal indicating that the reservoir has been drained and refilled. A controller responds to the counter having a first threshold value by activating an annunciator to alert the operator that is it time to change the water. Thereafter when the counter has a greater second threshold value and the controller disables operation of the warewasher until the sensor indicates that the reservoir has been drained and refilled. Thus the operator is required to change the water in order to continue using the warewasher.

Claims

1. A method for controlling operation of a warewasher, said method comprising:

detecting a condition of the warewasher that requires corrective action;

alerting a human operator of the condition that requires corrective action;

monitoring an operational parameter of the warewasher to provide an indication when the corrective action occurs;

if the corrective action does not occur, disabling subsequent operation of the warewasher; and

in response to the monitoring indicating occurrence of the corrective action, enabling operation of the warewasher.

2. The method as recited in claim 1 wherein detecting a condition of the warewasher comprises:

counting operations of the warewasher to produce a count; and

determining an occurrence of the condition when the count has a predefined value.

3. The method as recited in claim 1 wherein monitoring an operational parameter comprises sensing a characteristic of the warewasher that indicates draining and refilling a reservoir.

4. The method as recited in claim 3 wherein sensing a characteristic of the warewasher comprises sensing electrical conductivity within the reservoir.

5. The method as recited in claim 4 wherein the occurrence of the corrective action is indicated by the electrical conductivity having a first value and then having a second value that is greater than the first value.

6. The method as recited in claim 3 wherein sensing a characteristic of the warewasher comprises sensing a level of water within the reservoir.

7. The method as recited in claim 6 wherein the occurrence of the corrective action is indicated by the water dropping below a predefined level and then rising above the predefined level.

8. The method as recited in claim 1 wherein detecting a condition of the warewasher that requires corrective action comprises sensing temperature of water within a reservoir;

and determining that the temperature is less than a given value.

9. The method as recited in claim 8 further comprising, after alerting the operator:

counting operating cycles of the warewasher; and

wherein disabling subsequent operation of the warewasher occurs if a predetermined number of operating cycles take place while the temperature is less than the given value.

10. The method as recited in claim 1 wherein detecting a condition of the warewasher that requires corrective action comprises sensing exhaustion of a detergent in a dispenser connected to the warewasher.

11. The method as recited in claim 1 wherein detecting a condition of the warewasher that requires corrective action comprises sensing exhaustion of a chemical in a dispenser connected to the warewasher.

12. A method for controlling operation of a warewasher that has a reservoir for water, said method comprising:

counting operations of the warewasher to produce a count;

sensing at least one characteristic of the warewasher that indicates draining and refilling the reservoir; and

responding to the count having a predefined value by disabling operation of the warewasher until the sensing indicates that the reservoir has been drained and refilled.

13. The method as recited in claim 12 wherein the sensing comprises sensing electrical conductivity within the reservoir.

14. The method as recited in claim 13 wherein after disabling operation of the warewasher, the operation is enabled upon the electrical conductivity having a first value and then having a second value that is greater than the first value.

15. The method as recited in claim 12 wherein sensing comprises sensing a level of a fluid within the reservoir.

16. The method as recited in claim 15 wherein after disabling operation of the warewasher, the operation is enabled upon the fluid dropping below a predefined level and then rising above the predefined level.

17. The method as recited in claim 12 further comprising activating an annunciator in response to the count, thereby alerting a human operator of a need to change the water in the reservoir.

18. The method as recited in claim 17 wherein the annunciator is activated in response to the count having a given value which is less than the predefined value.